In hospitals, clinics, and other health care facilities, a wide variety of medications and other pharmaceuticals are administered to patients by oral ingestion. Oral administration generally requires that a pharmaceutical dose be deposited in a vial in the pharmacy of the health care facility, from which it is transported to the patient and ultimately administered. This procedure provides many opportunities for contamination, spillage, or outright tampering, since efficient operation of the pharmacy makes it desirable to pre-fill a number of vials of a given medication at one time, though use may be spread out over an entire day or even several days. If the vials are sealed at the time of filling, the patient or the nurse may experience difficulty in opening a vial at the time of administration, depending upon the type of construction of seal employed. Contamination before, during and after filling is a persistent problem. Post-filling tampering, which may involve removal of part of the contents of a vial, dilution through addition to the contents of the vial, or even complete substitution, is often possible.
A number of different constructions are known for sealed vials. Most of these devices employ caps or closures of multi-part construction, involving a molded stopper of elastomer or resin material in conjunction with a clamping ring (usually metal) to hold the stopper in place. Additional elements, such as resin or metal covering discs, are commonly used in conjunction with the principal stopper and clamp ring. Access to the vial interior is frequently provided by a slit valve or other opening in the stopper. Devices of this kind are disclosed in Campbell U.S. Pat. No. 2,236,491, Breakstone U.S. Pat. No. 2,579,724, Roberts U.S. Pat. No. 2,797,837, Gould U.S. Pat. No. 3,013,687 Reimann U.S. Pat. No. 3,067,898, Hershberg et al U.S. Pat. No. 3,424,329, Wimmer U.S. Pat. No. 3,653,528, Westfall U.S. Pat. No. 3,690,499, Zackheim U.S. Pat. No. 3,823,840, and in Cantrill British Patent No. 602,763.
A unit dose vial used for oral administration of pharmaceuticals is described in Handman U.S. Pat. No. 4,244,478, issued Jan. 13, 1981; it provides an elastomer stopper which seals the vial and affords a rim covering the lip of the vial, together with a metal sealing ring crimped onto the vial and covering the stopper rim. The stopper has a self-venting self-sealing linear slit valve that allows filling of the vial with the stopper in place. The sealing ring includes an integral release tab permitting quick and convenient removal of both the ring and the stopper for oral administration of the vial itself.
Another container and closure assembly adaptable to unit dose vials is described in Miskin U.S. Pat. No. 3,595,420, issued July 27, 1971, in which an open-top vial is covered by a resilient molded cap that has an integral skirt encompassing the upper portion of the vial; the inner suface of the skirt and the outer surface of the vial have complementary mating interlock elements that preclude manual removal of the cap from the vial. The cap comprises a tear member defined by one or more weakened junction lines molded into the skirt. Removal of the tear member permits convenient removal of the cap from the vial at the time of administration.
These prior art devices commonly prevent contamination of the interior of the vial prior to and during filling. Frequently, the same devices also prevent casual contamination of the contents of the vial after filling. Indeed, this is true of most of the prior art devices noted above. The Miskin device, on the other hand, provides no protection for the vial before filling, but does prevent any post-filling tampering with the contents of the vial, whether by way of extraction from or addition to the vial.
Ideally, a vial intended for oral administration of pharmaceuticals should permit filling with the vial closure already in place to maintain the vial in clear and sterile condition. At the same time, the vial assembly should permit rapid and convenient removal of the vial cap, by either a nurse or a patient, for oral administration of the pharmaceutical. The vial and closure assembly also should prevent any casual contamination of the contents of the vial after it has been filled and should preclude tampering by addition to, removal from, or even complete substitution for the contents of the vial. These somewhat conflicting requirements have not been fully and effectively met in any single vial and closure assembly of the prior art.